https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118317
Bug ID: 118317 Summary: `len - (len != 0) + 1` should optimize to `len == 0 ? 1 : len` Product: gcc Version: 15.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: enhancement Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: pinskia at gcc dot gnu.org Target Milestone: --- Take: ``` unsigned bar(unsigned len) { unsigned t = len - (len != 0) + 1; return t; } unsigned bar1(unsigned len) { return len == 0 ? 1 : len; } ``` These 2 should produce the same code. For unsigned, MAX_EXPR could be used. Noticed while looking at PR 118316 on what LLVM was doing for the loop.